1.  theme song(n = noun.communication) signature, signature tune - a melody used to identify a performer or a dance band or radio/tv program;
is a kind of air, line, melodic line, melodic phrase, melody, strain, tune

2.  theme song(n = noun.communication) - a melody that recurs and comes to represent a musical play or movie;
is a kind of air, line, melodic line, melodic phrase, melody, strain, tune

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